Reducing Noise/Vibration from Trucks

[jacktripper]

I need to take some steps to reduce noise and vibration coming from large (semi) trucks which pass about 50ft from my house at high speed (35-40mph). The roadway is about 10 ft below the level of the house with a gradual slope.

I recognize that significant noise will remain. I just want to minimize it within my cost restraints (about $5000).

I am considering two steps. Please critique and offer suggestions.

First, I will add second windows to the windows facing the street. Does anyone know of a high quality, reputable manufacturer of noise abating windows? (perhaps airport grade). Should they be installed inside or outside of the existing windows?

Second, I will build a masonry wall parallel to the street. How thick? How tall (code restricts to 8ft)? What impact would this have on neighbors (would it reflect sound across street to make worse for them?)

Would these steps make a difference, or is the noise too great to reduce effectively?

Thanks.

Tommy

[Jim Thompson]

You'll probably still have noticeable vibration effects even with the window-treatment+wall. Heavy-truck noise is very low frequency and travels thru the ground.

...Jim Thompson

[Herb Singleton]

[snip]

1st thing: when you say "vibration" are you referring to low frequency noise ("rumble") or ground-borne vibration (shaking of the ground)? There is not much you as a homeowner can do to reduce ground-borne vibration from trucks other than to ask your city/town to smooth out the road surfaces or reduce the speed limit.

Are you sure that the windows are the "weak link" on that facade? Windows can help, but be sure that noise isn't coming through a vent or other openings.

A noise barrier should be made out of a material with a density of at least 4 lbs/sq foot. The wall should have no visible gaps - any gap will render the wall ineffective. The wall also needs to be high enough to block the line-of-sight between you and the noise source (the exhaust stack in you case).

You are correct that sound may reflect off the wall and increase traffic noise at your neighbor's property. There are methods to avoid this - however, without knowing the exact geometries involved, it's hard to say what would happen.

If you're serious about pursuing this, you might want to hire an acoustical consultant to advise you.

[Des Perado]

[Angelo Campanella]

There's no secret involved. The thicker the glass pane, the better. Consider at least 1/4" and up to 1/2" or more. The seal about the perimeter is important, and it should be attached to the masonry niche about the window and not to the window frame for best low frequency noise attenuation. If your house is ofmasonry construction, this will quell most of the "vibration" (which is relaly the walls and window reacting to the low frequency sound mpresure waves.

With masonry buildings, the best results come from installation in the niche as desribed. The inner location will be useful only if a high degree of sound attenuation is NOT needed, and you MUST install and remove from the inside.

At least two pounds per square foot (10 kg/m^2).

Not that they would particularly notice it, though visual perceptions can be powerful persuaders.

The heavy window in the niche is the best improvemtn.

Actually, the best PERFORMANCE would come from installing a thick plate glass pane OVER the niche (larger than the niche dimensions by 10 cm or more, captured by an external frame that is sealed to the masonry with grout. Ponderous and ugly, it will indeed be the "terminator" of sound penetration into your bedroom! (You essentiall build a transparent extension of your masonry materal over the opening.

Angelo campanella.

[b&k]

This link may shed some light on the situation. Doesn't sound like a DIY project though!

[Tom Miller]

I know nothing about this subject myself, but here's a website with lots of info:

[me]

Just place some tack strips across the road. Put them a mile down the road in each direction, and no trucks will make it to your home. Total cost will be about $20 (not including the jail sentence you get if you are caught). Therefore, hire the mentally ill kid down the block to do it for you, he'll do it for a few popsicles, or just promise him a night in bed with Michael Jackson. . . ..........

[TesteeFreeze]

He should be glad he is ABOVE the road, it's worse BELOW the grade. I know that for fact, and I am a half mile away from the road. Yet, that sound just rumbles down the valley.

[CBhvac]

I thought this was a serious post, until I saw the 35-40MPH called high speed...

Snip

[jacktripper]

Thanks for the info. With regard to the wall, you note that any gaps in the wall will render it ineffective. One challenge is that I would have to leave a 10ft opening in the wall to allow car access to the driveway. Would this render the wall useless? It would seem to me that the wall would perform its function except when the trucks pass the opening for the driveway. Thanks.

[Herb Singleton]

It's pretty hard to say what's going to happen without knowing the geometries involved. You're right that the wall will help to block noise when the truck is behind it. However, since noise will propagate to your home when the trucks pass the gap, you may not subjectively notice the noise reduction. But again, it really depends on the geometries involved.

[b]

I live by a train. Low speed and no night horns is ignored with trains and more so with trucks.

Trees and bushes. The roots should help absorb the ground shake. Start watering.

[Herb Singleton]

Maybe the above posting is just a troll, but just in case someone does take it seriously, I want to say that the advice is completely wrong.

[Kari Pesonen]

Not completely wrong. Trees and roots have an effect on ground borne vibration attenuation (in surface and near surface layer). Effect/efficiency depends, e.g., on soil quality. I remember a German study from 1970's (?) concerning use of trees as a toned vibration absorbers. The frequency of max. absorption (damping) depended on tree (trunk) height. Unfortunately I could not find this paper from my files.

Kari Pesonen

[b]

The original poster was probably new to the neighborhood. After a few years he will get used to it. A sound proof room would be good to meditate and play some kick ass jam.

Farmers have used trees and shrubs to stop soil erosion and break the wind. Sound is carried by wind.

Roots have minimal absorbtion.

Herb is located in Boston. They do not have very good luck with trees there. I lived there for 5 years. Very costly to maintain and the sound will easily bounce off other buildings.

[Bill Marshall]

I have nothing to add to the topic under discussion. However, based on Kari's encylopedic recall of the relevant literature on almost any acoustical subject, the phrase "my files" produced a vivid mental image. I saw a room lined with floor-to-ceiling bookcases, Kari standing on a rolling ladder, reaching for a folder.

-- Bill Marshall

To reply, replace "***" with "_J_" in my return address.

[Eric Desart]

Hello Bill,

I indeed believe that Kari must have one of the best organized Acoustic Databases in existance, maybe combined with a superior memory.

This is meant as complement.

Eric

[BJ Nash]

The link with some information on this is at

($5k is not gonna do it).

BJ

[SQLit]

Here in Phoenix they put in sound walls that were 10-14 feet high, when the road is recessed slightly from the surroundings. If your stuck with 8' walls then why not try a hedge, Greenery absorbs sound and cuts the dust. I an not aware of any laws about planting shrubs on their height. Set back will probably apply, check with your building authority. Ditch the second windows and try replacements of double or triple glazed. I have a friend that installed them on his block home one block away from a busy street, level. There was an noticeable improvement. I have a block home and had the walls sprayed with foam 3 years ago, best grand I ever spent. I still have single glazed windows and the house became much quieter.

You do not mention where you are in the country, so I am just tossing idea about.